/*ident "@(#)cls4:lib/complex/complex/abs.c 1.3" */
/*******************************************************************************
C++ source for the C++ Language System, Release 3.0. This product
is a new release of the original cfront developed in the computer
science research center of AT&T Bell Laboratories.
Copyright (c) 1993 UNIX System Laboratories, Inc.
Copyright (c) 1991, 1992 AT&T and UNIX System Laboratories, Inc.
Copyright (c) 1984, 1989, 1990 AT&T. All Rights Reserved.
THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE of AT&T and UNIX System
Laboratories, Inc. The copyright notice above does not evidence
any actual or intended publication of such source code.
*******************************************************************************/
#include <complex.h>
#include "const.h"
double
abs(complex z)
{
register double temp;
register double r = z.re;
register double i = z.im;
if (r < 0) r = -r;
if (i == 0) return r;
if (i < 0) i = -i;
if (r == 0) return i;
if (i > r) { temp = r; r = i; i = temp; }
temp = i/r;
temp = r*sqrt(1.0 + temp*temp); /*overflow!!*/
return temp;
}
double
norm(complex z)
{
register double r = z.re;
register double i = z.im;
#define SAFE 6.521908912666391000e+18 /* 0.5*sqrt(GREATEST)*/
if (r<SAFE && i<SAFE) return r*r+i*i;
return GREATEST;
}
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